Renewable energy systems are technologies that can generate electricity from solar, wind, hydroelectric, biomass, and other renewable energy resources. This research project aims to find the best renewable energy technology combinations for several scenarios in Malaysia. The strategies are analysed by evaluating the investments in the renewable energy systems in each of the decided scenarios in Malaysia, Pekan, Pahang and Mersing, Johor, using HOMER Pro software. The finding shows that the PV–wind hybrid system has a better net present cost (NPC) than the other systems for both scenarios, which are USD −299,762.16 for Scenario 1 and USD −642,247.46 for Scenario 2. The PV–wind hybrid system has 4.86-year and 2.98-year payback periods in Scenarios 1 and 2. A combination of RE technologies yielded fewer emissions than one kind alone. The PV–wind hybrid system provides a quicker payback period, higher money savings, and reduced pollutants. The sensitivity results show that resource availability and capital cost impact NPC and system emissions. This finding reveals that integrated solar and wind technologies can improve the economic performance (e.g., NPC, payback period, present worth) and environmental performance (e.g., carbon dioxide emissions) of a renewable energy system.

Renewable energy resources especially wind energy, have seen significant growth in the worldwide energy market as clean energy sources. This has brought attention to areas with low and moderate wind speeds. Small-scale Darrieus vertical axis wind turbine (VAWT) with omnidirectional capability captures potential energy in these areas at a cost-effective scale. Numerous studies have been conducted to optimise their design, hence improving the performance of these turbines. Turbine solidity, σ, representing the ratio of the overall area of the blades over the swept area of the turbine, is one of the influential geometrical factors that significantly affect wind turbine performance. Previous studies on solidity focused on the number of blades and blade length variations, while the study on turbine diameter is limited. Hence, this paper intends to numerically investigate the effect of solidity that corresponds to different turbine diameters. Power performance and flow characteristics are investigated closely according to different solidity, σ and tip speed ratios, λ using high-fidelity computational fluid dynamic (CFD) method, which solves the unsteady Reynolds-Averaged Navier-Stokes (RANS) equations. Solidity and tip speed ratios vary within a wide range of 0.3 – 0.7 and 0.5 – 4.5, respectively. The results show that decreasing the turbine solidity from 0.7 to 0.3 could significantly increase the maximum power coefficient, Cp, by 30%. However, turbine with high solidity (σ = 0.7) generate much higher instantaneous moment coefficient, Cm than the low solidity turbine (σ = 0.3), but at lower λ and a narrower range of λ. The difference in turbine's performance between high and low solidity turbine is attributed to stall experienced by the blade at low λ and the blockage effect experienced by the turbine at moderate to high λ that significantly influence the energy generation at downstream region

Alternative energy is a rapidly expanding research area primarily driven by concerns over pollution caused by inefficient conventional energy sources. However, many developing nations rely heavily on these conventional sources. In response, numerous researchers have focused on developing kinetic energy recovery systems (KERS) to capture and utilize the energy lost due to inefficiency. These KERS can be implemented in various scenarios, such as near railroad tracks, industrial flue stacks, cooling towers, and air conditioning outlets. The primary objective of this paper is to critically and comprehensively evaluate the research conducted on the development of these systems. The review reveals that the wind speed in the studied cases ranged between 15 and 22 m/s, providing a consistent and theoretically maximum potential higher than any location worldwide. Furthermore, the impact of these systems on the Betz limit, as well as their drawbacks and crucial advancements necessary for practical implementation, have been thoroughly assessed. This paper contributes to the existing body of knowledge by presenting a comprehensive analysis of the research conducted on KERS development. It highlights the potential of these systems in harnessing untapped energy sources and identifies key areas that require further attention for successful practical application.

With the escalating demand for energy, there is a growing focus on decentralized, small-scale energy infrastructure. The success of new turbines in this context is notable. However, many of these turbines do not follow many of the basic ideas established to evaluate their performance, leaving no precise technique or mathematical model. This research developed a Ducted Horizontal-axis Helical Wind Turbine (DHAHWT). The DHAHWT is a duct-mounted helical savonius turbine with a venturi and diffuser to improve flow. Unlike a vertical axis helical savonius turbine, DHAHWT revolves roughly parallel to the wind, making it a horizontal turbine. This complicates mathematical and theoretical analysis. This study created a DHAHWT mathematical model. COMSOL simulations utilizing Menter’s Shear Stress Transport model (SST) across an incoming velocity range of 1m/s to 4m/s were used to evaluate the turbine’s interaction with the wind. MATLAB was used to train an artificial neural network (ANN) utilizing COMSOL data to obtain greater velocity data. The Mean Average Percentage Error (MAPE) and Root Mean Square Error (RMSE) of ANN data were found to be 3%, indicating high accuracy. Further, using advanced statistical methods the Pearson’s correlation coefficient was calculated resulting in a better understanding of the relationship of between incoming velocity and velocity at different sections of the wind turbine. This study will shed light on the aerodynamics and working of DHAHWT.